> p = (1, 2)

> from collections import namedtuple
> Point = namedtuple('Point', ['x', 'y'])
> p = Point(1, 2)
> p.x
1
> p.y
2

> isinstance(p, Point)
True
> isinstance(p, tuple)
True

# namedtuple('名称', [属性list]):
Circle = namedtuple('Circle', ['x', 'y', 'r'])

> from collections import deque
> q = deque(['a', 'b', 'c'])
> q.append('x')
> q.appendleft('y')
> q
deque(['y', 'a', 'b', 'c', 'x'])

> from collections import defaultdict
> dd = defaultdict(lambda: 'N/A')
> dd['key1'] = 'abc'
> dd['key1'] # key1存在
'abc'
> dd['key2'] # key2不存在，返回默认值
'N/A'

> from collections import OrderedDict
> d = dict([('a', 1), ('b', 2), ('c', 3)])
> d # dict的Key是无序的
{'a': 1, 'c': 3, 'b': 2}
> od = OrderedDict([('a', 1), ('b', 2), ('c', 3)])
> od # OrderedDict的Key是有序的
OrderedDict([('a', 1), ('b', 2), ('c', 3)])

> od = OrderedDict()
> od['z'] = 1
> od['y'] = 2
> od['x'] = 3
> od.keys() # 按照插入的Key的顺序返回
['z', 'y', 'x']

from collections import OrderedDict
class LastUpdatedOrderedDict(OrderedDict):
 def __init__(self, capacity):
  super(LastUpdatedOrderedDict, self).__init__()
  self._capacity = capacity
 def __setitem__(self, key, value):
  containsKey = 1 if key in self else 0
  if len(self) - containsKey >= self._capacity:
   last = self.popitem(last=False)
   print 'remove:', last
  if containsKey:
   del self[key]
   print 'set:', (key, value)
  else:
   print 'add:', (key, value)
  OrderedDict.__setitem__(self, key, value)

> from collections import Counter
> c = Counter()
> for ch in 'programming':
...  c[ch] = c[ch] + 1
...
> c
Counter({'g': 2, 'm': 2, 'r': 2, 'a': 1, 'i': 1, 'o': 1, 'n': 1, 'p': 1})